Study On The Influence Of Blocking Explosion-Proof Material On Explosion Of Oil-Gas Mixture

In the process of urbanization in China,many problems have arisen concerning the planning and layout of oil and gas transportation pipelines and urban pipeline networks and residential areas.For example,oil and gas transportation pipelines and underground canals and municipal pipeline networks are relatively close and overlapping,and even oil and gas transportation pipelines are suspended and erected in drainage culverts.Once these oil and gas pipelines leak,they will flow directly into drainage.Culverts seriously threaten people's lives and property security.This paper is a sub-project of the National Natural Science Foundation project "Explosion Mechanism and Prevention of Oil-Gas Mixed Gas in Urban Drainage Culverts"(51474151).It mainly studies the barrier effect of explosion-proof materials on round gas explosion.The explosion propagation characteristics of oil-gas mixture and the influence of barrier explosion-proof materials on the explosion characteristics of oil-gas mixture were studied experimentally.The main conclusions are as follows:(1)The explosion limits of methane and gasoline were measured,in which the explosion limits of methane were 5%-14%,which were basically in accordance with the theoretical values;the explosion limits of gasoline were 3%-12%,which were different from the theoretical values.The analysis may be related to the reasons of the experimental equipment itself.(2)The maximum explosion intensity of methane and gasoline was obtained through experiments.The maximum explosion intensity was 1.51 MPa and 19.65 m/s when the concentration of methane was 9%.The maximum explosion intensity was 1.46 MPa and explosion pressure was 32.54 m/s when the concentration of gasoline was 4.2%.(3)Through the experimental study of the explosion of oil-gas mixture gas in the experimental pipeline,the rule of the explosion of the mixture gas in the pipeline is obtained.The flame propagation velocity increases first and then decreases along the pipeline,and reaches the maximum at 0.6m from the ignition end.The explosion pressure produces two peaks in the pipeline,the first peak coincides with the peak of the flame velocity,and the second peak is near the end of the pipeline.(4)Choose the concentration of different gases(gasoline + methane)for experiment.When the concentration of methane is less than 9%,the explosion intensity increases first and then decreases with the increase of gasoline concentration;when the concentration of methane is greater than or equal to 9%,the explosion intensity decreases gradually with the increase of gasoline concentration;if the concentration of gasoline remains unchanged,the law of increasing methane concentration is similar to that of gasoline.In the experiment of anti-explosion of explosion-proof material,the concentration of oil-gas mixture with relatively high explosion intensity was selected.In one group,methane concentration was high,9% methane was mixed with 0.6% gasoline;in the other group,gasoline concentration was high,2% methane was mixed with 4.2% gasoline.(5)Experiments were carried out with explosion-proof material filled in the experimental pipeline.The explosion pressure and flame velocity of flammable gas in the pipeline were attenuated obviously by explosion-proof material,which had obvious explosion suppression effect.If the density of control material is unchanged,the larger the proportion of material to pipeline,the more obvious the anti-explosion effect will be;if the proportion of control material to pipeline is unchanged,the greater the density of material,the more obvious the anti-explosion effect will be;if the quality of control material is unchanged,the anti-explosion effect will be little different if the proportion or density of material to pipeline is changed.